What are lectin receptors?
C-type lectin receptors (CLRs) are important pattern recognition receptors involved in recognition and induction of adaptive immunity to pathogens. Certain CLRs play an important role in viral infections as they efficiently interact with viruses.
Where are lectin receptors found?
dendritic cells
1.2 C-Type Lectin Receptors CLRs are mainly expressed on dendritic cells but also on other myeloid cells. They are characterized by a carbohydrate recognition domain which allows them to bind pathogen-associated carbohydrate motifs (Geijtenbeek and Gringhuis, 2009).
What do C-type lectin receptors bind to?
C-type lectin receptors (CLRs) comprise a large family of receptors that bind to carbohydrates in a calcium-dependent manner. The lectin activity of these receptors is mediated by conserved carbohydrate-recognition domains (CRDs).
What are lectins immune system?
Lectins are glycan-binding proteins that are involved in numerous biological processes including cell development, cell–cell interactions, signaling pathways, and the immune response. Main classes of lectins in innate immunity include C-type lectin receptors (CLRs), siglecs, and galectins.
How lectins recognize cell surface receptor?
By virtue of C-type lectin domains, these receptors mediate adhesion by recognizing specific carbohydrate-based ligands on partner cells. Additionally, several leukocyte receptors, for which lectin activity has been demonstrated or inferred to exist, will be considered briefly.
How do antigen presenting cells recognize antigen?
An antigen-presenting cell (APC) or accessory cell is a cell that displays antigen bound by major histocompatibility complex (MHC) proteins on its surface; this process is known as antigen presentation. T cells may recognize these complexes using their T cell receptors (TCRs).
What do Collectins do?
Collectins (collagen-containing C-type lectins) are a part of the innate immune system. Collectins are soluble pattern recognition receptors (PRRs). Their function is to bind to oligosaccharide structure or lipids that are on the surface of microorganisms.
How lectins recognize cell surface receptors?
What is the main function of lectins?
Lectins have a role in recognition at the cellular and molecular level and play numerous roles in biological recognition phenomena involving cells, carbohydrates, and proteins. Lectins also mediate attachment and binding of bacteria, viruses, and fungi to their intended targets.
Why are bacterial lectins important for the infection process?
Lectins mediate adhesion of microorganisms to host cells or tissues, which is a prerequisite for infection and/or symbiosis to occur. Consequently, lectin-deficient microbial mutants are often unable to initiate infection.
How do lectins bind to sugars?
Lectin interacts with sugar or glycan residues with a unique binding domain known as the carbohydrate recognition domain (CRD) comprised of about 120–160 amino acids. They can hold more than one simple sugar in their binding sites because of their structural similarity.
What does lectin do to cell growth?
Conclusions. Lectins can be used as mitotic agents on T lymphocyte cultures to stimulate cell proliferation initiating by their cross-linking with TCR on cell surface. This interaction may lead to the activation of specific signaling pathways that induce cells to enter into DNA replication of cell cycle.
What is the lectin pathway?
The lectin pathway is responsible for an antibody-independent pathway of complement activation that is initiated by binding of the mannose-binding lectin (MBL) to carbohydrates on the surface of pathogens.
What is a C type lectin receptor Quizlet?
Overview of Pathogen- or Damage-activated C-type Lectin Receptor Signaling Pathways. C-type lectin receptors (CLRs) are a large family of soluble and transmembrane proteins that contain one or more distinct protein folds known as C-type lectin-like domains (CTLD).
How do lectin receptors activate innate immune cells?
C-type lectin receptors (CLRs) bind to carbohydrate moieties of endogenous and exogenous origin, trigger phagocytic responses, and activate innate immune cells, particularly of myeloid origin. The binding specificity for some of these receptors has been elucidated and includes fungal, bacterial, mycobacterial, viral, and parasitic ligands.
What is MBL (mannose binding lectin)?
Mannose-binding lectin (MBL), also known as mannan-binding protein (MBP), is a protein that is involved in complement activation via the lectin pathway. The complement system provides immediate defense against infection and has proinflammatory effects. MBL deficiency has been variously defined as a serum levels either <100 or <500 ng/mL.